A pre-amplifier (PA) is an erbium-doped fiber amplifier (EDFA) used to improve the signal receiver sensitivity at the receive end. The PA is located before the demultiplexer (DEMUX) and after the line amplifier. In Wavelength Division. Optical Amplifier (OA) is an important composition in WDM Transmission Network, it amplifies optical signals. TARLUZ Optical Amplifiers featured with real-time, high gain, broad width, on-line, low noise, and low attenuation. It is an essential component in a new-generation optical fiber. The optical module serves as a crucial component in optical fiber communication systems, operating at the physical layer, which is the lowest layer in the OSI model. There are two main product types BA (Booster Amplifier) and PA. DWDM technologies, which also have been considered as the most cost-effective ways to increase the network capacity over long transmission distance, have been widely applied in telecommunication network.